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Why you should care about the Libertarian Party in 2016

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The third party candidates head into the town hall with a lot to prove

Here are five things to watch

(CNN)The year is 2016, and a third party is going to prime time.

The Libertarian presidential candidate, former New Mexico Gov. Gary Johnson, and his running mate, former Massachusetts Gov. Bill Weld, will face voters Wednesday evening in a town hall live on CNN.

The 9 p.m. event moderated by CNN's Chris Cuomo marks one of the highest-profile moments in the Libertarian Party's history, thanks to Donald Trump, whose victory in the GOP presidential primary has some conservatives and moderates alike looking elsewhere for an alternative to both Trump and Democrat Hillary Clinton.

Still, in CNN's live format, surrounded by questioning voters, Johnson will have to do his best to connect with as many people as possible, as credibly as possible.

What Johnson preaches is a relaxation of government involvement in all spheres. He wants to do away with government regulations, cut budgets and replace the tax code with an unorthodox tax plan called FairTax. He also wants to legalize marijuana, embrace gay rights and do away with gun laws.

For liberals and conservatives, this cross-cutting, grab bag of hard-line policy stances is heretical, even fringe. If Johnson and Weld can push through decades of Democratic and Republican messaging, they must start now.

Knocking Trump

The opportunity for a Libertarian breakthrough in 2016 rests largely on the idea that voters who can't stomach Trump or Clinton will go somewhere else.

Trump's campaign has been a whirlwind of controversy and combat. As the Republican primary showed, there is plenty to attack when it comes to Trump. The question is how Johnson and Weld approach him.

Johnson has wavered between saying he would kill Trump with kindness and suggestion he would insult the mogul personally. In an interview on CNN just after he clinched the Libertarian nomination, Johnson blew a kiss at Trump.

But showing a more combative side, Johnson had repeatedly called Trump a "p-ssy" in a NowThis video from CPAC, a conservative conference in March.

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Shortly after his announcement that he was joining up with Johnson, meanwhile, Weld compared Trump's immigration policy to Kristallnacht, literally the "Night of Broken Glass," a pogrom within Nazi Germany.

In repeated interviews with CNN, Weld has likened Trump's rise to the rise of the Nazis, calling the Republican presumptive nominee's immigration proposals a "slippery slope."

"I've studied Nazi Germany and the rise of the Nazis," Weld said. "I do think that Mr. Trump has been demonizing them (undocumented immigrants), and that is partly what happened in Europe in the '30s and '40s."

Contrasting with Clinton

When it comes to attacking Clinton, Johnson has drawn a contrast between his worldview and hers.

Johnson is a skeptic of foreign military interventions. Clinton has a record supporting them. He has argued that major U.S. involvement in global affairs has only increased tension and violence the world over. Clinton been a key figure helping to shape U.S. foreign policy for years.

"I do think that Hillary has been the architect of what is happening worldwide, and I don't think the world is any safer today," Johnson said in an interview on CNN's "New Day."

Don't expect much on Clinton's scandals, either. Weld dismissed the controversy over Clinton's email practices in a February interview with Boston Herald Radio, saying, "I've never bought that email thing... I know her well, and I don't think she would lay a lot of stuff out on the table that she thought would compromise our national security."

Attacking Clinton over this area -- one that Trump and many Republicans have focused on -- would either be a change of heart or a change of tack for Johnson's running mate. It could also be an indication the two of them intend to go at Clinton with everything they can.

Balancing act

Johnson and Weld have to appeal to Republican voters who think Trump isn't a true conservative and Democratic voters who think Clinton is not liberal enough. It's a tough balancing act.

"We don't have to say we're anti-Trump or anti-Mrs. Clinton," Weld said in an interview with CNN's Michael Smerconish. "All we got to do is come out of the block saying we don't agree with either party."

Some of their work has already been done for them when it comes to pulling support from the Republican Party.

2012 Republican nominee Mitt Romney, like Weld a former Massachusetts Republican governor, indicated he was open to supporting the Libertarian bid. His problem, however, was with Johnson's support of marijuana, which he said, "makes you stupid."

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Johnson pushed back on Romney's assertion, but if he can appeal to bonafide GOP establishment figures, his longshot bid could become slightly more realistic.

But the Libertarians are also going after the polar opposite of people like Mitt Romney: die-hard supporters of Bernie Sanders, the Vermont senator who challenged Clinton from the left. Socially liberal and skeptical of the Washington establishment, these voters could swing towards Johnson.

Johnson has said he favors abortion rights, is pro-gay and anti-drug war. Until recently he was even the CEO of a company selling cannabis. On the political quiz site iSidewith.com that he often touts, Johnson said the candidate he matches with most, besides himself, is Sanders.

But many of Sanders' voters were drawn to the democratic socialist's unabashedly progressive economic message. On that score, Johnson isn't budging. He has espoused a near absolute preference for free market policies. Sanders' calls for increased regulation, taxation and government benefits are anathema to Libertarians.

Commander-in-chief test

It has come to pass that the Libertarian presidential ticket, the one that wants to stamp out government, is the one with the most executive governing experience in the entire election.

Johnson and Weld, both two-term Republican governors in blue states, will have to demonstrate that they are ready to occupy the nation's highest office.

"I've been an entrepreneur my entire life, and I was the two-term governor of New Mexico, and I think I was a successful governor," Johnson said.

Both Johnson and Weld are sharply skeptical of the drug war and have invoked their respective experience on the matter. Johnson was a border governor and made his opposition to the war on drugs one of his signature issues. Weld nearly served as President Bill Clinton's ambassador to Mexico, but abandoned the bid after squaring off with Jesse Helms, an arch-conservative Republican senator from North Carolina.

On other matters, they have touted their record opposing their former party, the GOP, on all manner of issues including foreign policy.

Johnson has moved to make himself appear more ready for the task of leading the nation's armed forces. For example, he said he has quit indulging in THC-laden edibles so he will be fully alert in the Oval Office, whatever the hour.

The former New Mexico governor has pushed back against people who call him or the Libertarian Party "isolationist," saying instead that he favors diplomacy. He has cited North Korea's nuclear weapons program as a particular area of concern and advocated a diplomatic approach, involving pressure on the Chinese.

People will need to see if he can translate his messages of diplomatic support and concern into action.